Pianist Billy Childs is on a constant quest to find music that can't be labeled as, say, "bop" or "new age." He tends to write what he calls "jazz chamber music" for a sextet that comprises guitar, harp, sax, drums, piano and bass.

But he appeared, live and unplugged, in a trio format with Dave Carpenter (bass) and Steve Houghton (drums) at the Athenaeum Music & Arts Library on Saturday, July 7, and this did not seem to cramp his style one bit.

Amplification may seem superfluous at the intimate book-lined venue although, despite being a veteran of Woody Herman's Herd, Houghton admitted that a drummer faces some real challenges working without a monitor speaker behind him to let him know what the pianist is doing.

From the audience's point of view, Childs did wonderful things to the music of Duke Ellington, George Shearing and Bill Evans.

The trio breezed through Shearing's "Conception," and two Evans compositions "Three Four Skidoo" and "One For Helen." Each was deconstructed with ingenious simplicity in improvisations that were, by turns, slow and gentle or hard and fast.

Ellington's "Sophisticated Lady" turned out mellow as ever but remarkably fresh. The piano's sensitive introduction established the analytical tone and a smartly descending scale in Carpenter's solo gave a cool examination of the possibilities presented by the song's chords.

Childs' classical background and his six years as a Freddie Hubbard sideman leave him equipped to offer an arrangement of "Scarborough Fair" that wasn't remotely corny. Also a brief cover of John Coltrane's "Giant Steps," with the benefit of 40 years' hindsight seemed to ask Cedar Walton what all the fuss was about.

The cool version of "Scarborough Fair", with its arabesque trills and swirling flourishes, was borrowed from the book of Childs' chamber sextet. His arrangement of the standard, "Alone Together" and his own composition, "Just Another Day," may be found on one of his CDs, "The Child Within," released on Shanachie Records in 1996.

The other original compositions: "A Fleeting Instant," "In Carson's Eyes," "Four by Five," and "Hope in the Face of Despair" did not seem out of place in the company of more conventional songs. If they can't be classed as hard bop, they certainly didn't scream "experimental" or "avant garde" to the Athenaeum faithful.

The Jazz Trios series continues on Saturday July 14 with Darrell Grant (piano), Dmitri Matheny (flugelhorn) and Ruth Davies (bass). Grant and Matheny have appeared together on major concert stages from the Weill Recital Hall at Carnegie Hall to the Monterey, Telluride and San Francisco jazz festivals. Grant has built an international reputation, touring in the 1980s and 90s in the bands of Betty Carter, Woody Shaw, Tony Williams, Frank Morgan, Sonny Fortune, Chico Freeman, Don Braden, Vincent Herring and Roy Haines.

A rising star celebrated for his warm, romantic tone and soaring lyricism, Matheny was privately mentored for ten years by legendary flugelhorn master Art Farmer. Matheny has made guest appearances on 20 recordings and has released five critically-acclaimed CDs, including the superbly atmospheric 1998 "Starlight Café" featuring Darrell Grant.

The final concert, on Thursday July 26 with Jeff Hamilton (drums), Tamir Hendelman (piano) and Christoph Luty (bass), is already sold out.

Admission is $15 to members and $17 non-members. Both concerts begin at 7:30 at the Athenaeum Music & Arts Library, 1008 Wall Street, La Jolla. Call (858) 454-5872 for reservation waiting-list information.